1. Field of the Invention
The present invention relates to Location-Based Services, and more particularly, it relates to a system for a multi-level MS-assisted Location trigger and a service method thereof.
2. Description of the Related Art
Location-Based Services (LBS) utilize a geographical location of a mobile station (MS) and provide location-specific services. There are hybrid technologies to obtain information based on a current location of a networked MS (or its user), and herein, a Global Positioning System (GPS) equipped MS is required to use the LBS.
Such an LBS utilizes a geographic location of an MS (or its user) in various marketing fields including a theater, a shopping mall, or a restaurant, using a cellular phone or a GPS. The LBS may provide more accurate information, and further it may be applied to networked fields and/or be combined with various positioning technologies including a Geographic Information System (GIS) and the GPS.
The LBS includes mobile station, trigger event, emergency call, public zone, point meeting, and location-sensitive billing services, and so on.
In particular, the mobile station service provides a user with geographical information, vicinity of a pre-specified area, traffic information, tourism information, and a friend finding service, etc., based on a current location of the MS (or its user). As examples of the LBS, SK Telecom provides their Mobile Zone service, and KTF provides information on traffic. In addition, the trigger service enables tracking of an MS (or its user) or a tracking-device-equipped subject in real-time by receiving a current location of the MS or the current location of the subject from an LBS server, and various types of services can be hybridized therefrom. The emergency call service provides prompt location identification in cooperation with the 911 Emergency or a criminal investigation department (i.e. Enhanced-911 in the United States). The public zone service reports entrance/exit from a restricted area of the MS by a short message service (SMS) or an e-mail, and provides various services in cooperation with a CRM server. The point meeting service provides on-line chatting and off-line meeting with another MS (or its user) located in the vicinity through a blind date service and wireless Internet. Further, a location-sensitive billing service provides an MS (or its user) with a selective payment method depending on a current location of the MS (i.e., home, work, shopping zone, etc.).
Meanwhile, “An apparatus for informing mobile communication terminal of its position and method thereof” disclosed in Korea Patent No. 2001-16733 filed on Mar. 30, 2001, provides a detecting method of a location trigger in a visitor location register (VLR).
In this prior invention, a particular area is pre-specified and a subscriber who enters the pre-specified area is provided with services based on the location. The purpose of the invention is to inform a new subscriber of their entering/exiting of the pre-specified area. The apparatus for informing a mobile communication terminal of its position and the method thereof provides a subscriber with information on whether the subscriber enters a pre-specified location where associated services based on the location are available, thereby utilizing location-based services in various ways.
“Message method for destination arrival of terminal” disclosed in Korean Patent No. 2002-48735 filed on Aug. 17, 2004, provides a method of messaging destination arrival to a mobile terminal (or its user), wherein the mobile terminal includes a mobile telephone or a GPS.
The message method for destination arrival of the mobile terminal according to the invention provides a method of visually or aurally informing a user of arrival at the destination when the user falls asleep or reads a book while traveling by public transport.
Hereinafter, a method for supporting a location trigger function in a conventional location-based service (LBS) will be described, with reference to FIG. 1 to FIG. 3.
Extending the functionality of a Mobile Services Switching Center (MSC)/Home Location Register (HLR) is one of the methods for supporting the location trigger in the conventional LBS.
FIG. 1 shows an exemplary embodiment of configuring the location trigger by extending the functionality of the MSC/HLR, and exemplarily describes implementation of the location trigger by extending the functionalities of an HLR and a Visitor Location Register (VLR), which is carried out by SK Telecom (a mobile telecommunication provider in South Korea).
As shown therein, the most general method of the location trigger in the conventional LBS is directly modifying the HLR and VLR of the base station in a mobile network for supporting a roaming service.
A process sequence of setting up the location trigger is as follows.
{circle around (1)} An operator of a location trigger inputs information (i.e., base station information) through an information input/output device 161 of a location information service system 160, and stores the inputted information in a user-trigger area database 162. The user-trigger area database 162 informs of regional data update to a location change controller 163.
{circle around (2)} The location change controller 163 transmits the updated trigger information (base station) to an HLR 150, and the HLR 150 stores the updated trigger information and transmits the information to MSCs 130a and 130b. 
{circle around (3)} The MSCs 130a and 130b mark a particular field (i.e., a particular location-based service field) among stored location information as ‘1’ using the transmitted trigger base station information.
Further, an operation sequence of the location trigger is as follows. {circle around (1)} Changes of base stations 121a, 121b, and 121c or a current location of an MS 110 are updated to VLRs 140a and 140b in the MSCs 130a and 130b managing base stations, and the MSCs detect the changes.
{circle around (2)} Herein, the MSCs 130a and 130b determine whether the new location is within a pre-specified area where the particular location-based service field value is set, and information related to the new location of the MS 110 is transmitted to the location change controller 163 through the HLR 150 when the new location is within the pre-specified area.
{circle around (3)} The location change controller 163 searches the user-trigger area data base 162 using the information on the MS 110 to check whether the MS 110 is registered with particular location-based services, and whether the MS meets pre-defined trigger criteria. In the case that the MS 110 satisfies both conditions, the MS information is provided to a location trigger user.
The foregoing method has advantages of implementing the location trigger regardless of type of MS by extending the functionality of the MSC and HLR, but at the same time causes direct modification of exchange software (i.e., MSC) and communication interruption when the trigger location function is overly activated, thereby inducing the exchange to be overloaded.
On the other hand, a polling server can be employed to support the location trigger function of the conventional LBS.
FIG. 2 illustrates a configuration of the location trigger employing a conventional pooling server.
The location trigger can be implemented by constantly and periodically monitoring a current location of an MS 210 using a polling server 263 periodically requesting the current location of the MS until satisfying pre-specified conditions in a user-trigger location database 262.
Meanwhile, a polling method using a mobile positioning center (MPC) server also can be employed to support the location trigger function of the conventional location-based services.
FIG. 3 shows a method of configuring a location trigger employing a conventional Mobile Positioning Center (MPC) server.
Recent network communication systems employ a Position Determination Entity (PDE) and a Mobile Positioning Center (MPC) in compliance with an increasing number of Assisted-GPS equipped MS users and telecommunication standardization carried out by the 3GPP. Herein, the PDE is a system containing an algorithm to position the A-GPS equipped MS (i.e., MSM5xxxx developed by Qualcomm), and the MPC is an integrated gateway system providing location-based information related to external wireless Internet services.
However, there are problems to be solved in the foregoing conventional technologies. The MSC performs a main role in the communication network and is implemented by directly modifying base station equipment, such as an HLR and a VLR supporting an MS roaming service. Further, direct modification of exchange software (herein, the MSC) is also required, and communication interruption occurs when trigger location function is overly activated, thereby inducing the exchange to be overloaded.